A New Study
A new study out by the University of Bristol who examined the case of a young patient’s blindness, determined that poor nutrition can lead to optic neuropathy, vision problems and vision loss.
“An extreme case of “fussy” or “picky” eating caused a young patient’s blindness, according to a new case report published today in Annals of Internal Medicine.”
Nutritional Optic Neuropathy
Nutritional optic neuropathy is a dysfunction of the optic nerve which is important for vision. The condition is reversible, if caught early. But, left untreated, it can lead to permanent structural damage to the optic nerve and blindness.
In developed counties, the most common cause of optic neuropathy are bowel problems or drugs that interfere with the absorption of nutrients. Strictly dietary causes are rare because food supplies are typically good. Elsewhere food supplies may not be because of poverty, war and drought.
Clinician scientists from Bristol Medical School and the Bristol Eye Hospital examined the case of a teenage patient who first visited his GP complaining of tiredness. The link between his poor nutrition and vision was not picked up until much later, and by then, his visual impairment had become permanent.
Signs and Symptoms
Besides being a fussy eater the patient was found to have a normal BMI, height with no visible signs of malnutrition. They also took no medications. The patient was found to have macrocytic anemia and low B12 levels, all of which were treated with injections and dietary advice. When the patient returned to the GP a year later the patient’s vision had worsened Further investigation found the patient had vitamin B12 deficiency, low copper and selenium levels, a high zinc level, and markedly reduced vitamin D level and bone mineral density. Since starting secondary school, the patient had developed poor nutrition by consuming a limited diet of chips, crisps, white bread, and some processed pork. By the time the patient’s condition was diagnosed, the patient had permanently impaired vision.
Researchers concluded that a poor diet and not enough nutrition in the way of vitamins and minerals resulted in nutritional optic neuropathy. They believe the condition could become much more prevalent in the future given the widespread consumption of junk foods and a rising popularity of a vegan diet that is not supplemented appropriately to prevent B12 deficiency.
Dr Denize Atan, the study’s lead author and Consultant Senior Lecturer in Ophthalmology at Bristol Medical School and Clinical Lead for Neuro-ophthalmology at Bristol Eye Hospital, said:
“Our vision has such an impact on quality of life, education, employment, social interactions, and mental health. This case highlights the impact of diet on visual and physical health, and the fact that calorie intake and BMI are not reliable indicators of nutritional status.”
The Bristol team recommends that dietary histories should be part of any routine clinical examination like asking about smoking and alcohol intake. This may avoid a diagnosis of nutritional optic neuropathy being missed or delayed as some associated visual loss can fully recover if the nutritional deficiencies are treated early enough.
Sources: University of Bristol
- Rhys Harrison, Vicki Warburton, Andrew Lux, Denize Atan. Blindness Caused by a Junk Food Diet. Annals of Internal Medicine, 2019; DOI: 10.7326/L19-0361
University of Bristol. “Poor diet can lead to blindness, case study shows.” ScienceDaily. ScienceDaily, 3 September 2019. <www.sciencedaily.com/releases/2019/09/190903091437.htm>.
For more helpful eye care and vision care tips, please visit our main blog page.